Metodyka studiów litofacjalnych przy poszukiwaniu złóż ,ropy naftowej i gazu ziemnego

Abstract

METHODS OF FACIAL STUDIES IN SEARCH FOR OIL AND GAS DEPOSITS

Summary

Investigation of lithologic-facial development of deposits, that particularly take into account the possibilities of occurrence of porous reservoir rock horizons and of impermeable and sealing series in the mother rocks for oil and gas, are necessary in search for oil and gas deposits. These problems are solved by means of lithofacial studies, the results of which are as a rule presented in the form of various lithofacial maps. The article presents the technique of making the so-called index maps, exemplified here by a lithofacial map of the Dogger deposits from the Polish Lowland area. As a basis for this map served here the computations of the clastic ratio, examined for the individual drillings, that reflects the relation of terrigenous rocks to calcareous-dolomite rocks, and of the clay-sand ratio that shows the relation of thickness of arenaceous rocks to clay-siltstone series. Basing on the triangle diagram and on the course of isolines of both ratios, nine areas characterized by various percentage of all groups examined in the profiles have been distinguished. The method here. considered represents one of the simplest quantitative methods of maps, and may be of considerable importance for Polish geology in various kinds of researches